1. Field
The present general inventive concept relates to an apparatus and method of detecting a horizontal synchronization signal of an image forming apparatus.
2. Description of the Related Art
Image forming apparatuses form images on printing media according to input signals, for example, printers, copying machines, faxing machines, and multifunctional devices combine functions of printers, copying machines, and faxing machines.
Tandem-type image forming apparatuses adopt an electrophotographic image forming method. Generally, a tandem-type image forming apparatus include a photosensitive medium, the number of which corresponds to the number of colors used in a printing operation. Since a color image forming apparatus generally uses toners of four colors, that is, yellow, magenta, cyan, and black colors, the tandem-type image forming apparatus includes four light sources and four photosensitive media, which respectively correspond to the four color toners.
Therefore, the color image forming apparatus forms an electrostatic latent image by focusing laser beams emitted from the four light sources according to image signals on photosensitive media corresponding to each of light sources. Here, a horizontal synchronization signal is used to coincide light scanning times of the four colors, and four photosensors are required to detect the horizontal synchronization signal from each of the colors. Therefore, there is a need to simplify a structure of an image forming apparatus and reduce fabrication costs by detecting the horizontal synchronization signal of each color with a small number of photosensors.